rc.firewall quick change

[Julian Elischer]

Julian Elischer wrote:
> Ian Smith wrote:
>> On Thu, 13 Nov 2008, Julian Elischer wrote:
>>  > At home I use the following change.
>>  >  >  > basically, instead of doing 8 rules before and after the nat,
>>  > use a table and to 1 rule on each side.
>>  >  >  > any objections?
>>
>> Only that if people are already using tables for anything, chances are 
>> they've already used table 1 (well, it's the first one I used :)  How 
>> about using table 127 for this as a rather less likely prior choice?
> 
> yes I thought of that..
> in fact it should be ${BLOCKTABLE} and let the user define what he 
> wants. (defaulting to 99 or something).
> Remember though that a user wouldn't be using 'simple' if he's using his 
> own tables etc.
> 

so here's a slightly improved diff:

-------------- next part --------------
Index: rc.firewall
===================================================================
--- rc.firewall	(revision 184948)
+++ rc.firewall	(working copy)
@@ -216,11 +216,13 @@
 	#  firewall_simple_inet:	Inside network address.
 	#  firewall_simple_oif:		Outside network interface.
 	#  firewall_simple_onet:	Outside network address.
+	#  firewall_block_table:	Table to use blocking stuff.
 	############
 
 	# set these to your outside interface network
 	oif="$firewall_simple_oif"
 	onet="$firewall_simple_onet"
+	tbl=${firewall_block_table:-99}
 
 	# set these to your inside interface network
 	iif="$firewall_simple_iif"
@@ -231,19 +233,24 @@
 	${fwcmd} add deny all from ${onet} to any in via ${iif}
 
 	# Stop RFC1918 nets on the outside interface
-	${fwcmd} add deny all from any to 10.0.0.0/8 via ${oif}
-	${fwcmd} add deny all from any to 172.16.0.0/12 via ${oif}
-	${fwcmd} add deny all from any to 192.168.0.0/16 via ${oif}
+	${fwcmd} table ${tbl} add 10.0.0.0/8
+	${fwcmd} table ${tbl} add 172.16.0.0/12
+	${fwcmd} table ${tbl} add 192.168.0.0/16
 
 	# Stop draft-manning-dsua-03.txt (1 May 2000) nets (includes RESERVED-1,
 	# DHCP auto-configuration, NET-TEST, MULTICAST (class D), and class E)
 	# on the outside interface
-	${fwcmd} add deny all from any to 0.0.0.0/8 via ${oif}
-	${fwcmd} add deny all from any to 169.254.0.0/16 via ${oif}
-	${fwcmd} add deny all from any to 192.0.2.0/24 via ${oif}
-	${fwcmd} add deny all from any to 224.0.0.0/4 via ${oif}
-	${fwcmd} add deny all from any to 240.0.0.0/4 via ${oif}
+	${fwcmd} table ${tbl} add 0.0.0.0/8
+	${fwcmd} table ${tbl} add 169.254.0.0/16
+	${fwcmd} table ${tbl} add 192.0.2.0/24
+	${fwcmd} table ${tbl} add 224.0.0.0/4
+	${fwcmd} table ${tbl} add 240.0.0.0/4
 
+        # Stop the above nets with the table
+
+	${fwcmd} add deny all from any to "table(${tbl})" via ${oif}
+
+
 	# Network Address Translation.  This rule is placed here deliberately
 	# so that it does not interfere with the surrounding address-checking
 	# rules.  If for example one of your internal LAN machines had its IP
@@ -260,19 +267,8 @@
 	esac
 
 	# Stop RFC1918 nets on the outside interface
-	${fwcmd} add deny all from 10.0.0.0/8 to any via ${oif}
-	${fwcmd} add deny all from 172.16.0.0/12 to any via ${oif}
-	${fwcmd} add deny all from 192.168.0.0/16 to any via ${oif}
+	${fwcmd} add deny all from "table(${tbl})" to any via ${oif}
 
-	# Stop draft-manning-dsua-03.txt (1 May 2000) nets (includes RESERVED-1,
-	# DHCP auto-configuration, NET-TEST, MULTICAST (class D), and class E)
-	# on the outside interface
-	${fwcmd} add deny all from 0.0.0.0/8 to any via ${oif}
-	${fwcmd} add deny all from 169.254.0.0/16 to any via ${oif}
-	${fwcmd} add deny all from 192.0.2.0/24 to any via ${oif}
-	${fwcmd} add deny all from 224.0.0.0/4 to any via ${oif}
-	${fwcmd} add deny all from 240.0.0.0/4 to any via ${oif}
-
 	# Allow TCP through if setup succeeded
 	${fwcmd} add pass tcp from any to any established